The model NP231 transfer case is a compact, chain-driven transfer case manufactured by New Venture Gear (New Process Gear) in Syracuse, New York. Since the early 80's, the model 231 has been used in many vehicles and is designated as follows: NP231C = GM S-10, S-15 trucks & Blazers 1983 - 1991, NP231D = Dodge midsize and fullsize trucks, NP231J = Jeep YJ's, TJ's, and some XJ's. This transfer case was first introduced in Jeep Wranglers in 1988 after replacing a 1-year run of NP207 transfer cases.
All "J" models of the NP231 are not created the same. There are internal differences among different year models and this kit has been designed to be compatible with each version. Our fixed yoke kit has been installed in hundreds of V8 equipped Wranglers (small block and big block) to date without a single shaft failure. Because of this success, the new output shaft carries a Lifetime Replacement Warranty.
Mega Short SYE Slip Yoke Eliminator Kits w Speed Sensor NP231 87-06 Wranglers
This kit is a MUST if you installed a 2" or taller suspension lift in your 1987-2006 Jeep« Wrangler (not needed for body lifted Jeeps«). The kit fits all newer production NP 231 transfer cases (1987- up). A Slip Yoke Eliminator Kit (SYE) will eliminate the need to drop your transfer case in order to avoid drivetrain vibrations that are caused by taller suspension lift. The purpose of this kit is to replace the slip yoke portion of the NP 231 with a fixed yoke and CV-style drive shaft assembly. This is the most complete and strongest kit available. The Mega Short SYE (18676.72) is designed to be used in the same lift applications as the other standard SYE kit (2" and up). The main advantage to the new Mega Short SYE kit is that it allows for a much longer drive shaft to be used (additional 3"). This reduces the angle of the dive shaft and in turn improved bearing and u-joint life, reduces driveline vibrations caused by lifted Jeeps running short drive shafts. It also has a shorter and stronger main shaft design.
Fits the following Jeep Models:
87-95 Jeep YJ Wranglers
97-06 Jeep TJ Wranglers
84-01 Jeep XJ Cherokees